| Zugriffsnummer | 33367 |
| Dokumenttyp | Zeitschriftenartikel |
| Peer Review | unbekannt |
| Sprache | Englisch |
| Titel | Quantification of variable functional-group densities of mixed-silane monolayers on surfaces via a dual-mode fluorescence and XPS label |
| Autor(in); Institution |
Fischer, Tobias; BAM - Federal Institute for Materials Research and Testing, Berlin, GERMANY
Dietrich, Paul M.; BAM - Federal Institute for Materials Research and Testing, Berlin, GERMANY
Streeck, Cornelia; 7.2, Kryophysik und Spektrometrie, PTB-Berlin; Helmholtz-Zentrum für Materialien und Energie, Berlin, GERMANY
Ray, Santanu; National Physical Laboratory (NPL), Teddington, UK
Nutsch, Andreas; 7.2, Kryophysik und Spektrometrie, PTB-Berlin; Helmholtz-Zentrum für Materialien und Energie, Berlin, GERMANY
Shard, Alex; National Physical Laboratory (NPL), Teddington, UK
Beckhoff, Burkhard; 7.2, Kryophysik und Spektrometrie, PTB-Berlin
Unger, Wolfgang E.S.; BAM - Federal Institute for Materials Research and Testing, Berlin, GERMANY
Rurack, Knut; BAM - Federal Institute for Materials Research and Testing, Berlin, GERMANY
|
| Quelle/Jahr | Analytical Chemistry: 87 (2015), 5, 2685 - 2692 |
| ISSN | 0003-2700 (PRINT) ; 1520-6882 (ONLINE) |
| DOI | |
| Verlag | Washington, DC: ACS Publications |
| Freie Schlagworte | Amino silanes ; BODIPY dyes ; contact angle measurements ; fluorescence, surface group density ; total reflection X-ray fluorescence ; X-ray photoelectron spectroscopy |
| Zusammenfassung | The preparation of amino group-expressing monolayers with a controlled density of functional groups on silica surfaces through a simple vapor deposition process employing different ratios of two suitable monoalkoxy silanes, (3-aminopropyl)diisopropylethoxysilane (APDIPES) and (3-cyanopropyl)dimethylmethoxysilane (CPDMMS), and advances in the reliable quantification of such tailored surfaces are presented in this contribution. The one-step co-deposition process was carried out with binary silane mixtures, which renders possible the control over a wide range of densities in a single step. In particular, APDIPES constitutes the functional silane and CPDMMS the inert component. The procedure requires only small amounts of silanes, several ratios can be produced in a single batch, the deposition can be carried out within a few hours and a dry atmosphere can easily be employed which limits self-condensation of the silanes. The characterization of the ratio of silanes actually delivered and bound to the surface can then be performed in a facile manner through contact angle measurements using the Cassie equation. The reliable estimation of the number of surface functional groups was approached with a dual-mode BODIPY-type fluorescence label, which allows quantification by fluorescence and XPS on one and the same sample. We found that fluorescence and XPS signals correlate over at least one order of magnitude, allowing for a direct linking of quantitative fluorescence analysis to XPS quantification. Employment of synchrotron-based methods (XPS; reference-free total reflection X-ray fluorescence, TXRF) made the traceable quantification of surface functional groups possible, providing an absolute reference for quantitative fluorescence measurements through a traceable measurement chain. |
Zitierung
Fischer, T., Dietrich, P. M., Streeck, C., Ray, S., Nutsch, A., Shard, A., Beckhoff, B., Unger, W. E., & Rurack, K. (2015). Quantification of variable functional-group densities of mixed-silane monolayers on surfaces via a dual-mode fluorescence and XPS label. Analytical Chemistry, 87(5), 2685–2692. https://doi.org/10.1021/ac503850f